HDCI promotes green, sustainable and eco-friendly interior design and decorating that supports health and well-being. As the world becomes a more stressful place Holistic Design and Colour Therapy encourages people to extend their vision so they can live and work in stimulating, visually inspiring and healthy environments.

The Holistic Design Institute (HDI) was founded in 1992 by best-selling author and leading Holistic Interior Designer, colour psychology and Colour Therapy consultant, Suzy Chiazzari. The Institute has developed an excellent international reputation as a leading learning provider in the fields of creative and therapeutic arts using Colour Psychology and Colour Therapy, as well as environmental studies of Holistic Natural Interior design, Healing Garden design, Transformative Music and Sound Therapy and Creative Art as Therapy. Our distance learning courses can be used for personal or professional development as well as offering a creative and caring careers that honour and support the natural environment. Our beautiful International Diploma is awarded by the Holistic Design Institute U.K and can be used anywhere in the world.

Our home study courses are specially designed for home study by our principal, Suzy Chiazzari who is also an affiliate member of the Royal Institute of British Architects RIBA. Our distance learning courses are tutored by Suzy, who shares her experience and offers you sensitive support and comprehensive personal advice during your studies. All our courses have plenty of practical content so you become confident to work in your field of study when you graduate.


At the Iris International School of Colour we are passionate about colour and its ability to enrich and change lives. We believe that colour is a natural gift that we can all use to to help us through the stresses and challenges of life and it is our aim to help people to develop their sensitivity and understanding of colour’s spiritual and life-enhancing qualities.

The Iris School is proud that we are considered the leading training provider in the specialist field of colour and light as a healing tool to enhance self-development, health and well-being. All our accredited distance learning colour therapy courses were specially designed for home study and are tutored by Suzy Chiazzari herself, who is an internationally renowned bestselling author, teacher and colour therapy expert, who warmly shares her vast knowledge with you and gives you personal guidance and support during your studies. In her work Suzy combines colour psychology with other complementary health practices, including Counselling, Aromatherapy, Reflexology, Life Coaching and Spiritual healing and we offer many professional and short courses in all of these modalities.


World renowned professional training in growing and specialist fields of study.

Long established UKRLP registered and insured school based in the UK.

Beautiful accredited International Diploma so you can practice anywhere in the world.

Friendly and supportive tutoring and personal attention by Suzy Chiazzari, our principal.

Flexible start time and study at your own speed.

Choice of study mode by email, CD or lessons in workbooks (last option in UK only)

Easy to follow and comprehensive course lessons with other learning materials.

The course lessons are yours to download so you can refer to them whenever you want.

Simple assessment system.

Free one year practitioner membership to HDI and IWOC to our graduates.

After graduation support, mentoring and social media forums.

Eligibility for IGCT membership that offers practitioner insurance in UK, Canada and USA and IICT that provides insurance in over 39 countries.

Holistic Design Courses

The Holistic Design institute is a leading UKRLP registered online college that provides specialist training in Interior design, Garden design and Therapeutic Art and Music.

View our Holistic Design courses

Colour Therapy Courses

At the Iris School of Colour Therapy we are passionate about colour. We believe that colour is a natural gift that we can use to enrich ourselves, and to help us through the stresses and challenges of life.

View our Colour Therapy courses

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